drive: set all metadata permissions and return error summary

Before this change when setting permissions from the metadata rclone
would stop on the first error.

This change causes rclone to attempt to set all the permissions and
return an error summary at the end.

backend/drive/metadata.go

@@ -9,6 +9,7 @@ import (
 	"sync"
 
 	"github.com/rclone/rclone/fs"
+	"github.com/rclone/rclone/lib/errcount"
 	"golang.org/x/sync/errgroup"
 	drive "google.golang.org/api/drive/v3"
 	"google.golang.org/api/googleapi"
@@ -135,24 +136,26 @@ func (f *Fs) getPermission(ctx context.Context, fileID, permissionID string, use
 
 // Set the permissions on the info
 func (f *Fs) setPermissions(ctx context.Context, info *drive.File, permissions []*drive.Permission) (err error) {
+	errs := errcount.New()
 	for _, perm := range permissions {
 		if perm.Role == "owner" {
 			// ignore owner permissions - these are set with owner
 			continue
 		}
 		cleanPermissionForWrite(perm)
-		err = f.pacer.Call(func() (bool, error) {
-			_, err = f.svc.Permissions.Create(info.Id, perm).
+		err := f.pacer.Call(func() (bool, error) {
+			_, err := f.svc.Permissions.Create(info.Id, perm).
 				SupportsAllDrives(true).
 				SendNotificationEmail(false).
 				Context(ctx).Do()
 			return f.shouldRetry(ctx, err)
 		})
 		if err != nil {
-			return fmt.Errorf("failed to set permission: %w", err)
+			fs.Errorf(f, "Failed to set permission: %v", err)
+			errs.Add(err)
 		}
 	}
-	return nil
+	return errs.Err("failed to set permission")
 }
 
 // Clean attributes from permissions which we can't write